The significance of age group, gender and skin complexion in relation to the clinical distribution of developmental oral mucosal alterations in 5-13 year-old children.

INTRODUCTION: To describe the relationship and impact of age group, gender and skin complexion on the prevalence and clinical distribution of oral mucosal alterations of developmental origin (OMA-DO) among school children aged 5-13 years. METHODS: A randomized representative national survey of Jordanian school children including all Country geographic areas was performed. Cut-off age that significantly correlated with presence and distribution of OMA-DO was identified (ROC curve). Skin complexion was classified into light/fair, intermediate/tan, dark/brown based on skin complexion index. Chi square test with P value≤0.05 was used for significance of correlations. RESULTS: Two thousand two hundred and fifty one children were clinically examined. The average age that significantly correlated with prevalence and distribution of OMA-DO was 9.9 years. Female gender was significantly correlated with four OMA-DO: leukoedema (L), linea Alba (LA), Fordyce's granules (FG), commissural lip pits (CLP) and wider distribution of racial pigmentations (RP) (P<0.05, χ2 test). Older age group (9.9-13 years) was significantly correlated with 7 OMA-DO: L, LA, FG, frenal tag, CLP, mandibular and maxillary tori (MT) as well as wider clinical distribution of RP, FG, L (P<0.05 χ2 test). Dark skin complexion significantly correlated with 5 OMA-DO: L, LA, FG, RP, MT and wider clinical distribution of RP (P<0.02, χ2 test). CONCLUSIONS: Increased prevalence and wider clinical distribution of OMA-DO are significantly associated with older age group of 9.9-13 years, female gender, and dark skin complexion. Oral health care provides are encouraged to be familiar with these correlations. This knowledge is expected to improve OMA-DO diagnosis and clinical management. Continuous education programs in this field are recommended.

Entoconulid (cusp 6), metaconulid (cusp 7), post-metaconulid and pre-entoconulid expression on permanent mandibular first molar in the living Jordanian population and inter-trait interactions.

OBJECTIVES: To determine the frequency of expression and sexual dimorphism of the following dental morphological traits on the permanent mandibular first molar (LM1) in the living Jordanians: Entoconulid (cusp 6; tuberculum sextum), metaconulid (cusp 7, tuberculum intermedium), post-metaconulid and pre-entoconulid (entostylid) traits. In addition, to analyze inter-trait interactions whenever possible was one of the aims. METHODS: Three hundred sixty school children (176 males, 184 females, ages 15.5 +/- 0.4 years) from the middle of Jordan were involved. Impressions for the mandibular dental arches were taken, and dental casts were produced in 2009. The above-mentioned traits were observed. Z-value test between two proportions and nonparametric correlation analysis were used for data analysis. RESULTS: Cusp 7 on LM1 was found in 15.83 %, while cusp 6 on this tooth was found in 21.67% of the examined students. In comparison, both post-metaconulid and pre-entoconulid traits were found to be absent on LM1 in all observed subjects. Nonparametric correlation analysis revealed weak negative and statistically insignificant association between the expression of cusp 6 and 7 on LM1 among the living Jordanians. CONCLUSION: Both cusp 6 and cusp 7 on LM1 are expressed in a relatively higher rate among the living Jordanian Arabs than other studied Western Eurasians, suggesting a significant gene flow from Sub-Saharan Africans and Mongolians to the Middle East. In addition, the insignificant weak correlation between cusp 6 and 7 on LM1 suggests that these two dental morphological traits are both genetically and phenotypically independent.

Construction and use of facial archetypes in anthropology and syndrome diagnosis.

This paper describes the benefits of moving from recording simple Euclidian distances and angles between landmarks on the face to full three-dimensional visualisation and mapping using modern optical scanning techniques. Pilot experiments are reported on that strive to create facial archetypes which are accurately descriptive of various cohorts of people. Issues considered include variation amongst people of the same sex, age and population-of-origin. The study has discovered that very few people are needed to construct an "average" face, which is measurably indistinguishable from another average constructed using the faces of other people from within the group studied. This discovery has given the researchers confidence in the reliability of the archetypes which they have produced and this is important if such an analytical technique is to find application in discriminating between peoples on a population basis and in syndrome diagnosis.